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mkde (version 0.1)

writeRasterToVTK: Write a 2D raster to XDMF XML wrapper and binary data file.

Description

Write the raster to a XDMF files.

Usage

writeRasterToVTK(elev, r.rst, g.rst, b.rst, descr, fname)

Arguments

elev
A RasterLayer object
r.rst
A RasterLayer object for red
g.rst
A RasterLayer object for green
b.rst
A RasterLayer object for blue
descr
String description to be added to header of VTK file
fname
The path and base file name for output HDF5 files

Value

No value is returned

Details

This function writes a raster to VTK format. The raster is colored according to the RGB values in r.rst, g.rst, and b.rst, respectively. The RGB balues must be an interger from 0 to 255.

Examples

Run this code
library(raster)
data(condordem120)
elev.val <- values(condordem120)
elev.min <- min(elev.val, na.rm=TRUE)
elev.max <- max(elev.val, na.rm=TRUE)

# make a color lookup table
cmap <- data.frame(value=c(0.0, 0.25, 0.5, 0.75, 1.0), 
  R=c(150, 179, 205, 192, 252), 
  G=c(224, 204, 205, 183, 243), 
  B=c(94, 147, 168, 147, 226))
                    
cmap$value <- cmap$value*(elev.max - elev.min) + elev.min
# red
f.R <- approxfun(cmap$value, cmap$R)
elev.r <- raster(condordem120)
values(elev.r) <- round(f.R(elev.val))
# green
f.G <- approxfun(cmap$value, cmap$G)
elev.g <- raster(condordem120)
values(elev.g) <- round(f.G(elev.val))
# blue
f.B <- approxfun(cmap$value, cmap$B)
elev.b <- raster(condordem120)
values(elev.b) <- round(f.B(elev.val))
writeRasterToVTK(condordem120, elev.r, elev.g, elev.b, "Elevation for
California condor Example", "condor_dem.vtk")

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